Electric switching device and mounting means therefor



June 20, 1939. H R N 2,163,398

ELECTRIC SWITCHING DEVICE AND MOUNTING MEANS THEREFOR Filed Nov. 50,1937 Inventor: B enjamin R. Hermann,

y w m His ULor'ney Patented June 20, 1939 UNITED STATES PATENT OFFICEELECTRIC SWITCHING DEVICE AND- MOUNTING MEANS THEREFOR Benjamin It.Hermann, Lanesboro, Mass, assignor to General Electric Company, acorporation of New York Application November 30, 1937, Serial No.177,244 14 Claims. (01. 200 114) The present invention relates toelectric switchmanually moving the door and fuse holder into ing devicesand mounting means. therefor and and out of operative position. The doorand has for an object the provision of a simple and fuse holder aresupported in the casing by means low cost switching device of theenclosed type of a hinge lever 24 one end of which is pivotally havingimproved construction and arrangement attached to door boss 21, asindicated at 25, and 5 of parts and improved mounting means for intheother end of which has a hook-shaped porstallation of the devicedirectly upon a bushing tion 26 arranged to engage a hinge pin 21carsupported terminal of a transformer or like ried by hinge bracket 28.The hinge lever norpiece of electric apparatus. mally is held in rigidrelation to fuse holder l4 Other objects and the details of that which Iby means of a portion 35 of a fuse link extend- 10 believe to be noveland my invention will become ing out of the lower end of the fuse holderand apparent from the following description and the secured to the leverby any suitable form of claims appended thereto taken in conjunctionclamping means indicated at 35. With this with the accompanying drawingin which Fig. 1 arrangement, upon rupture of the fuse link in 5illustrates a rear view of an exemplary switchfuse holder M, the doorand fuse holder drop ing device, in the form of an enclosed fusecutdownwardly and outwardly to a position wherein out, and mountingmeans therefor embodying the fuse holder is isolated from upper contactll, my invention; Fig. 2 is a longitudinal oross-secthis operation beingin a manner similar to that tion through the housing of the cutoutshowing described in detail in connection with the dropthe constructionand arrangement of the parts out fuse cutout of my patent No. 2,081,813,issued 20 thereof; Fig. 3 is a detail view of an improved May 25, 1937,and assigned to the assignee of mounting bracket employed in supportingthe the present invention.

cutout; and Fig. 4 illustrates diagrammatically Hinge bracket 28 servesas the lower terminal the manner of mounting the cutout and bracketcontact of the cutout and forms part of an elecon a transformer terminalbushing. trically conductive bolt 32 which extends out- 25 Referring tothe drawing, Hi designates a caswardly through an opening in the rearwall of ing of porcelain or other suitable insulating rnacasing l0 andwhich is fixedly anchored in the terial in which is mounted an upperterminal opening by means of suitable cement, indicated contact llhaving spring fingers :2 adapted to at 33. The outer end of this bolt isthreaded for receive therebetween the upper terminal of a reception of aclamping nut 34 and a lock washer 30 switching element, such as theterminal cap is 35 and is arranged to extend through an openof aninsulating fuse holder l4. Contact II has ing 36 in the web portion 3?of a mounting also a. contact finger l5, backed by a spring stripbracket 38, which web portion 31 is adapted to IE arranged to beardownwardly on a fuse holder bear against the rear face of easing l0, asindi- 35 terminal cap. Although a fuse holder is emcated in Figs. 1 and2. 35 ployed in the exemplary embodiment illustrated, Mounting bracket38, the details of which are it will be evident from the ensuingdescription shown in the perspective view of Fig. 3, is comthat thepresent invention is not limited to this prised of any suitable metalhaving springiness particular form of switching element. For exandresistance to vibration fatigue failure. This {0 ample, an electricallyconductive switcl nng blade bracket is formed with a substantially flatand may be substituted for the fuse holder if it is de relatively thinportion 39 having an upper reinsired, as is sometimes the case, toemploy the forcing ridge 40 and a lower reinforcing ridge 4i. switchingdevice only for connecting and dis In the outer end of portion 39 is asocket openconnecting purposes without fuse protection. ing 42 disposedsubstantially in the plane of por- 45 Just beneath contact II is anelectric creepage tion 39 and adapted to receive a terminal stud 45 andgas barrier ll formed integrally with the 43 of a transformer or likepiece of electric appacasing and arranged to retard the rising of arcratus and to rest upon the upper end of the gases from the lower end ofan expulsion fuse terminal supporting bushing 44, as shown in Figs.holder, such as the one illustrated, into the space 1 and 2.

around the contact H in the upper part of the Casing I0 is clamped, bymeans of bolt 32, nut 50 housing. The illustrated fuse holder I4 is sup34 and washer 35, so that the rear face of the ported by bosses 2t and2| formed integrally with casing bears tightly against the lower face ofweb a door 22, constructed of suitable insulation, 31. This web isarranged so that it lies in a which is adapted to close the open frontof casplane at an acute angle to the plane of the flat ing l0 and whichhas an eyelet handle 23 for portion 39 of the mounting bracket or, inother 55 words, so that it lies in a plane at an angle of less than 90degrees to a plane extending through terminal stud 43 normal to theplane of opening 42. As a result of this expedient, casing IQ issupported, as best shown in Fig. 2, so that it is tilted forward at anacute angle to a plane passing through the axis of terminal stud 43 sothat are gases discharged from the lower end of fuse holder 14 will notbe directed straight downwardly on to the lower end of bushing as andthe adjacent portion of the cover of the transformer Q5 (see Fig. 4) todamage the bushing or cause short circuiting arc-over between conductingparts. The forward tilting or" the casing also prevents leakage of rainwater into casing I when door 22 is normally closed and prevents theentrance of rain-sleet, and snow into the casing when the door is in itsopen dropped-out position previously referred to. Bracket 38 has spacedapart flanges es projecting from the lower face of web portion 37 of thebracket and arranged to receive the cutout casing therebetween toprevent rotation of the casing relative to the bracket about bolt 32.

As a further result of the formation of the bracket as previouslydescribed, the flat portion 39 lies in a plane substantially transverseto the axis of fuse holder M. Due to its relative thinness, portion 39of the bracket flexes resiliently upon recoil of the fuse holder due tofuse operation or upon slamming of the door, thus providing a cushioningeffect to prevent damaging shock to the supporting bushing M whichcommonly is of insulating ceramic material relatively easily damaged byshock. Reinforcing ridges 49 and 4| are arranged to give sufficientstiffness to the bracket for proper support of the cutout while at thesame time permitting the desired flexibility of portion 39 of thebracket.

Also, in accordance with the teachings of my copending application,Serial No. 176,271 filed November 24, 1937, and assigned to the assigneeof the present invention, it is preferable that bracket 38 be providedwith a plurality of slots 41 communicating with socket opening 42 andextending radially of the opening with the slots arranged in pairs andthe slots of each pair disposed diametrically opposite each other, asbest shown in Fig. 3. These slots are arranged to receive a keeperelement' lll extending through a transverse slot 49 in terminal stud B3to prevent rotation of bracket 38 about the terminal stud. By reason ofthe plurality of pairs of slots 41, it is possible selectively toposition the bracket and the cutout casing attached thereto so that thedoor 22 is readily accessible from a transformer supporting pole 5B orsimilar mounting structure and so that the lower discharge end of fuseholder I4 is directed outwardly over the side of the transformer, asindicated in Fig. 4. An added advantage of the forward tilting of thecasing when the cutout is mounted as shown in Fig. 4, is that a serviceman is protected from injury by gases discharged from the lower end ofthe cutout in case of fuse operation during servicing. With thearrangement described, the cutout casing may be mounted in any desiredmanner iin different transformer installations wherein the supportingpole and terminal bushing have different physical relationships withrespect to each other and the transformer casing.

In an installation of the type diagrammatically illustrated in Fig. 4,the lower contact of the cutout is connected to the transformer terminalper contact has secured thereto, as by means of a screw 5|, one end of aline lead indicated at 52. Also, contact I I may have secured theretoone end of a lead 53 extending from a lightning arrester indicated at 54as being mounted on the side of the transformer -45. Thus, there isprovided a unitary transformer assembly embodying both overcurrent andovervoltage protection.

From the foregoing description, it will be seen that the switchingdevice of my present invention provides a means for securing in outdoorinstallations, such as on rural type transformers and the like, animproved fusing protection with the advantages of the enclosed type fusecutout, including superior insulation, safety to service men, andweather protection, which advantages it is not possible to secure withthe line suspension fuse cutouts and bushing mounted open type fusecutouts of the type heretofore commonly employed. My invention providesalso an improved switching device of the enclosed type, which, whilehaving the advantages above set forth, still is of such simple and lowcost construction that it may be embodied to advantage with otherprotective equipment, such as a lightning arrester, in a transformerassembly of the unit type so as greatly to facilitate the installationof the transformer assembly on a pole or other suitable supportingstructure in the field.

What I claim as new and desire to obtain by Letters Patent of the UnitedStates is:

1. The combination with an electric switching device of the enclosedtype having an insulating housing with a pair of spaced terminalcontacts therein and means for supporting in the housing an electricswitching element connected between said contacts, of a springy mountingbracket of electrically conductive material secured to said housing andhaving means for attachment to a bushing supported terminal stud of atransformer or the like, and means providing electric connection betweenone of said contacts and said mounting bracket.

2. The combination with an insulating housing for an electric switchingdevice, of a contact mounted in the housing, an electrically conductivemounting bracket attached to the housing and provided with means forattachment to an electrically conducting support for the housing, and anelectrically conductive element mechanically and electrically connectedwith said bracket and extending into the housing, which said element isprovided interiorly of the housing with means for pivotally supportingan electric switching element for engagement with said contact.

3. The combination with an electric switching device of the enclosedtype including an insulating housing comprised of a casing having anopen front and a door movably mounted for closing said open front, of amounting bracket havinga substantially flat and relatively thin springypor tion provided adjacent one end with a socket opening lyingsubstantially in the plane of said flat portion and adapted to receive asupporting stud, said bracket having adjacent theother end of said firstmentioned portion a web portion disposed at an acute angle to the planeof said first mentioned fiat portion, and means securing said casing tosaid bracket with the rear face of the casing bearing against theunderneath face of said web portion, whereby said open front of thecasing is maintained in a plane tilted forward at an acute angle to theplane of said first mentioned fiat portion and said socket opening,

4, The combination with an electric switching device of the enclosedtype having a housing of insulation with spaced contacts mounted thereinand means for supporting an electric switching element connected betweensaid contacts, or" a mounting bracket for said housing having anattachment portion arranged to bear against the rear face of saidhousing and a pair of arms pro jecting from said attachment portion inspaced relation to each other for receiving said housing therebetween,and means for securing said housing in the seat provided by saidattachment portion and projecting arms.

5. In an electric switching device, an enclosing housing of insulation,a pair of spaced contacts mounted in the housing, hinge means forpivotally supporting an electric switching element in the housingconnected between said contacts, and an electrically conductive mountingbracket for said housing having means for attachment to a terminal studof a transformer or the like, one of said contacts having anelectrically conductive element extending exteriorly of said housing andconnected to said bracket for securing the housing to the bracket.

6. In an electric switching device of the enclosed type, a housing ofinsulation, spaced contacts mounted in the housing and hinge means forpivotally supporting a switching element in the housing removablyconnected between the contacts, one of the contacts having anelectrically conductive mounting element extending exteriorly of thehousing for attachment to a support for the housing.

'7. In an electric switching device of the enclosed type, a housing ofinsulation and a pair of contacts mounted in the housing, one of whichcontacts is provided interiorly of the housing with means for pivotallysupporting a switching element removably connected between the contactsand said one contact having an electrically conductive mounting elementextending exteriorly of the housing for attachment to a support for thehousing.

8. In an electric switching device of the enclosed type a housing ofinsulation, spaced contact means mounted in the housing and a mountingmember extending through a wall of the housing in fixed relationthereto, which said member is provided exteriorly of the housing withmeans for attachment thereof to a support for the housing and isprovided interiorly of the housing with means for pivotally supporting aswitching element removably connected between said contact means.

9. In an electric switching device of the enclosed type, a housing ofinsulation, an upper contact mounted in the housing, and a lower contactmounted in the housing, which said lower contact is provided interiorlyof the housing with a hinge bracket for the pivotal support of anelectric switching element and has an electrically conductive portionextending exteriorly of the housing for attachment to a support for thehousing.

10. In an electric switching device of the enclosed type, a housingincluding an insulating casing having an open front, a contact mountedin the housing, and an electrically conductive bolt fixedly mounted inthe rear wall of the housing in spaced relation to said contact, whichbolt has a threaded portion extending exteriorly of the housing forattachment thereof to a support for the housing and a portion extendinginteriorly of the housing provided with means for supporting an electricswitching element for removable engagement with said contact.

11. An electric switching device including in combination an enclosinghousing of insulating material, an electrically conductive mountingbracket for said housing having means for attachment to an electricallyconductive supporting stud and having also a web portion arranged tobear against one of the walls of said housing, a pair of contactsmounted in said housing, one of said contacts having means forsupporting an electric switching element in the housing connectedbetween the contacts and having also a portion extending exteriorly ofthe housing and connected with said web portion for securing the housingto said bracket, and means carried by said bracket for preventingdisplacement of the housing relative to the bracket.

12. In a housing for an electric disconnect switch, fuse cutout and thelike, a box-like casing of insulation having top, rear and side Wallsand an open front, which open front provides for manipulation of anelectric connection element to and from a connected position betweenspaced contacts mounted in the casing and which open front is adapted tobe closed by a removable door, and upper and lower contacts mounted inthe casing in substantially fixed spaced relationship for removableengagement by an electric connection element, one of which contacts hasan electrically conductive mounting element provided with means formounting attachment to an electrically conducting support for the cas-13. In an electric switching device, a box-like insulating casing havingtop, rear and side walls and an open front providing for manipulation ofan electric connection element to and from connected position betweenspaced contacts mounted in the casing, a door for closing said openfront, upper and lower contacts mounted in the casing in substantiallyfixed spaced relationship, one of Which contacts has an electricallyconductive mounting element provided with means for mounting attachmentto an electrically conducting support for the casing, and means forsupporting an electric connection element in the casing in connectedposition between said contacts, which said supporting means is arrangedto provide for movement of an electric connection element relative tosaid contacts to a disconnected position.

14. In an electric switching device, a box-like insulating casing havingtop, rear and side walls and an open front, a door for closing said openfront, an upper contact mounted in said casing, a lower contact mountedin the casing and having an electrically conductive mounting elementprovided with means for mounting attachment to an electricallyconducting support for the easing, and means including said lowercontact arranged to support an electric connection element in the casingin connected position between said contacts and to provide for movementof the electric connection element relative to said contacts to adisconnected position.

BENJANIIN R. HERMANN.

